1. Field of the Invention
This invention relates to a resin composition which can provide a molded article excellent in dielectric characteristics and dimension stability, and to a molded article obtained therefrom.
2. Description of Related Art
Due to the development in wireless information communication network represented by mobile communication (such as satellite communication appliance, mobile phone, and PHS, wireless LAN system), or automotive communication (such as ETC system and GPS for highways), a demand for an antenna to be used for information communication appliances has been rapidly increasing. Since there is a demand for reductions in size, weight, and cost of such an antenna, a molded article obtained from a thermoplastic resin is used in a base for an antenna (hereinafter, referred to as “antenna base”).
For producing the antenna, it is necessary to form a conductive layer to be used as an electrode on the antenna base. Since soldering, metal plating, or the like is employed as a means for forming the electrode, the antenna base is required to have durability that prevents the properties thereof from being impaired by the electrode formation means. In order to satisfy such characteristics, liquid crystal polyester has been attracted attention as a thermoplastic resin to be used for producing an antenna base. Since the liquid crystal polyester has both of high level of heat resistance and processability and is of low water absorption, the liquid crystal polyester improves not only the durability related to the antenna production but also durability during temporal use of the antenna.
On the other hand, in the above-mentioned information communication appliances, due to the achievement of higher density of information, conformity to information communication using electromagnetic wave in higher frequency band has been considered, and because of the consideration, there is an increasing demand for an antenna base that is excellent in dielectric characteristics.
As the dielectric characteristics required for the antenna base, high dielectric constant (characteristic of being highly dielectric) and low dielectric loss tangent with respect to electromagnetic wave in higher frequency band are of importance. The highly dielectric antenna base is not considerably reduced in antenna characteristics even when the antenna is relatively small, and the low dielectric loss tangent antenna base has a tendency to be increased in antenna gain. In order to obtain the highly dielectric antenna base, a method of using a highly dielectric material as a filler (hereinafter, referred to as “highly dielectric material filler”) and obtaining an antenna base from a resin composition containing the highly dielectric material filler and liquid crystal polyester has been employed. For example, a resin composition containing liquid crystal polyester and a ceramic powder is proposed as a resin composition which can provide a molded article having highly dielectric characteristics and low dielectric loss tangent (see, JP-A-2006-233118).